Undertale Adventures X Unit Tier List: S to B Ranks and Roles Explained

If your defense keeps collapsing in the same spot, the problem is usually the unit filling that job — not your upgrades. An Undertale Adventures X unit tier list solves that by telling you which characters cover the area-damage, boss-killer, crowd-control, and front-line roles that decide whether a wave leaks. This guide breaks down a community-built Undertale Adventures X unit tier list drawn from two public rankings that placed the same five characters in the top band and named the same substitutes underneath them. No guesswork, no measured DPS charts — just roles and the decisions they drive.

How the Undertale Adventures X Unit Tier List Is Built

This is not an official ranking. Community reports describe it as a role board assembled from two public lineups: a July 2025 ranking and an October 2026 table. The letters track agreement between those sources, not raw damage numbers.

Two details keep this honest. First, units that sources described only as early picks or joke picks were not given a letter, because no source assigned one to each name. Second, a letter reflects a job, not a damage score — a unit can be S tier for wave clear and irrelevant for boss damage.

Why "role" beats "power level"

Most tier list arguments happen because two players are grading different jobs. Sans stopping a grouped wave and Mettaton NEO deleting a single high-health enemy are not competing for the same slot. Read every row below as "field this unit when this specific thing is failing your run."

S Tier: The Units That Carry Runs

These five were named in the top band by both public lineups.

Sans is the classic answer to pack pressure. Player experience consistently frames him as the piece that stops grouped waves from reaching the end of the lane — a crowd-control job rather than a damage benchmark.

Asriel earns the S slot for flexibility. Both public tables call him an area-damage unit that works on packs and bosses, which matters because most rosters have units that are excellent in one phase and dead weight in the next. If you can only invest in one carry early, this is the profile to chase.

Mettaton NEO is the dedicated boss killer. Community reports call him the premier single-target option, matching a boss-killer grade from the earlier ranking. One caveat worth repeating: no damage number was published alongside that October 2026 grade, so treat the ranking as a role judgment, not a stat sheet.

Undyne the Undying fills the front-line job — durable damage that holds while everything behind her works. Papyrus is the late-game crowd-control and scaling pick, and community reports also tie him to the ultra rare slot of the August 2024 Snowdin banner.

A Tier: The Substitutes That Keep a Run Alive

A tier here means "both public tables graded this lower, and both named it as the backup for an S-tier role." That is a very useful category, because most players will not own every top-band unit.

Asgore is the named stand-in for the front-line slot. He tanks and hits single targets, so he covers the survival half of Undyne's job even if he does not fully replace the damage.

Muffet slows big groups so your area damage has a window to connect. She is the named crowd-control substitute for Papyrus, which makes her the natural pickup if you are still hunting the S-tier option.

Mettaton EX sits under Sans and Asriel in both tables and does the wave-clear job. If your runs end because trash mobs pile up rather than because a boss survives, this is the correct addition.

B Tier: Early and Situational Picks

B rows come from the October 2026 table alone. They are not bad units — they are units with a defined window.

Temmie is the classic opener: enough offense to clear the first acts, but community reports say the defensive scaling stops keeping up later. Plan to replace the slot rather than upgrade around it.

Greater Dog holds a line and contributes little else. Use it only when both front-line options are unavailable.

Building a Team From the Ranking

The fastest way to use any Undertale Adventures X unit tier list is to stop drafting by rarity and start drafting by job. Cover four jobs and most stages stop surprising you.

A few practical habits that follow from the table:

• Draft the backup first if you own neither. A covered role at A tier beats an empty role at S tier.
• Do not double up on one job. Two crowd-control units and no boss damage still loses to a single tanky enemy.
• Swap, don't rebuild. If a stage fails at the boss, change only the boss-damage slot and re-run.
• Re-test after every update. Balance changes move units between jobs more often than they change raw numbers.

What This Ranking Cannot Tell You

Two things are worth saying plainly, because they affect how much weight you give the letters.

The board is community-made, not developer-published, and it was not replayed after the October 12, 2026 experience update. The Roblox listing changed that day but the description did not, and no patch notes were posted — so a balance change could exist that this ranking does not show.

It also does not rank every unit. Characters described only as early or joke picks sit on their own pages without a letter, because the sources never assigned one. For platform-level context on how Roblox experiences are updated and listed, see Roblox's official site.

Treat the letters as a starting lineup and let your own clears confirm them.

FAQ

Is the Undertale Adventures X unit tier list official? No. Community reports tie the letters to a July 2025 ranking and an October 2026 lineup that named the same top five and the same main substitutes. The developer did not publish this board.

Did the October 12, 2026 update change the rankings? The listing was updated that day, but the description stayed the same and no patch notes appeared. A hidden balance change is possible, which is why re-testing your own clears matters more than trusting a static Undertale Adventures X unit tier list.

Which unit should I build first? If packs are ending your runs, start with Sans. If a single tough enemy is the wall, prioritize Mettaton NEO. If units die before they act, Undyne the Undying is the front-line answer.

What is the best substitute if I miss an S-tier unit? Asgore covers the front line, Muffet covers crowd control, and Mettaton EX covers wave clear. Those three are the named backups, which makes them the safest investments while you chase the top band.